Gary Johnson: 'Where is it written that voters' choices should be so limited? Certainly not in the constitution.' Photograph: David Goldman, Eric Goldman/AP

With the election only days away, it is a fair question to ask how many American voters are about to cast their votes for a candidate who doesn't really reflect their views? Why would they do that?

The answer is complex – and simple. The Republicans and Democrats have spent decades trading power back and forth between themselves, and in doing so, have managed to install a two-party duopoly that completely controls America's political process. This duopoly runs everything from how candidates qualify to get on the ballot, to who is invited to the only debates aired on national television, to, yes, the special-interest money that fuels their billion-dollar campaigns.

The consequences of this insider game? Too many voters approach Tuesday's election believing their choice is between a Republican and a Democrat, with no other real option. And why shouldn't they? The debates they have seen only included the Republican and the Democrat. The hundreds of millions of dollars' worth of TV ads they have seen are all about the Republican and the Democrat. And the news media? Well, they have bought into the whole scheme, with coverage that overwhelmingly portrays a two-party race.

There's a problem, though. This duopoly leaves tens of millions of Americans essentially disenfranchised. Polling shows that roughly one third of voters doesn't necessarily consider themselves Democrats or Republicans. Every election, they end up making a choice between what some would call the "lesser of two evils".

Where is it written that voters' choices should be so limited? Certainly not in the US constitution. Certainly not in the law. And certainly not because the voters themselves decided that the media, two massively well-funded political parties or anyone else should "preselect" their choices for them.

In Tuesday's election, the sizable portion of the American electorate that believes the time is past when our troops should have been brought home from Afghanistan doesn't have a "major-party" candidate who agrees with them. The millions who believe government is far too large and intrusive will be looking at major-party options that both support the Patriot Act and a National Defense Authorization Act, which inexplicably legalizes the indefinite detention of American citizens. And for those who care deeply about marriage equality, they won't see a major-party candidate who believes marriage discrimination violates basic constitutional rights.

On the most compelling issue of all in these difficult times, the economy, what do the two major parties offer? Vague assurances that they will balance the budget someday, years or even decades from now, quibbling over minor adjustments to a fundamentally flawed and corrupt tax system. And neither offers any real commitment to challenge monetary policies that are devaluing our currency by the day.

Where is the choice on election day for a candidate who will balance the budget now and propose the first substantial reform of the entire tax code in decades – scrapping taxes on income and replacing them with a single consumption tax that will create millions of jobs?

Giving the American people these choices is what my campaign for president is all about. Of our $16tn debt, almost equal amounts have been racked up under Republicans and Democrats. Our chronic involvement in costly and unnecessary wars has come through a progression of major-party administrations that seem to have little or no disagreements on foreign policy. Likewise, the truly alarming erosion of our civil liberties by the federal government has been an entirely bipartisan effort.

Americans deserve the opportunity to vote for a third choice: a candidate who is neither a product nor a proponent of a status quo that is clearly not working. My candidacy, the thousands of volunteer hours spent overcoming obstacles to ballot access, and the determination of our campaign to "crash the party" are all driven by the desire and, I believe, the imperative to break the two-party stranglehold.

It will not happen in one election. But like all significant movements in American history, it can start with one election if the disenfranchised "waste their votes" in significant enough numbers to become franchised again.

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